LONDON - London Fashion Week moved into high international gear Saturday with a debut collection from Barbadian pop diva Rihanna, a Native American-inspired show by Brazilian-born Issa and a host of other eclectic offerings.

No one went to Rihanna's Saturday night debut as a fashion designer expecting demure dresses set off with tasteful pearls.

So no one was surprised by the double-volume hip-hop music, smoke machines and champagne that greeted guests at the unveiling of her Rihanna for River Island collection.

And few were taken aback by the bad girl, rock chick styling of some of her clothes, with tight-fitting jersey outfits and dresses cut to show more than a bit of leg.

It was a fun, flattering collection aimed at young women, containing nothing shocking or outrageous from a singer who has been known to bring those elements to her live performances.

She provided some pop star glamour to an already glittering London Fashion Week, which will soon showcase the work of Vivienne Westwood, Burberry's Christopher Bailey, and Tom Ford.

Rihanna followed Brazilian-born Daniela Issa Helayel (better known as Issa), John Rocha, Julien Macdonald and others to centre stage on the second day of fashion week.

Much of the buzz Saturday was about Rihanna's first-even fashion collection. Many of her outfits had a simple, monochrome look — in off-reds, yellow, navy, black and other colours — and they were cut to look good on those blessed with a fit physique.

Some were satin, some jersey, and some of the short skirts were made with denim and matched with crop tops or T-shirts.

Rihanna also tried her hand at a few elegant, semi-sheer dresses that were predominantly black with white floral patterns.

The singer appeared unusually shy but happy in her brief appearance on the catwalk to take in the audience's applause. She wore a short black dress as she waved to her fans.

If Rihanna brought a touch of show biz royalty to the catwalk, Issa brought her gold-plated royal connections. She is one of the favourite designers of the Duchess of Cambridge, the former Kate Middleton, who helped bring Issa to the world's attention before her marriage to Prince William.

Issa toned down her usual tropical exuberance to pay homage to the designs associated with Native Americans, particularly the Navajo, in a more muted but elegant presentation.

"It's quite different for us," Issa said. "I was very inspired by American Indians, the Navajos, the feathers. The woman goes to Morocco, she's nomadic, she's far cooler than before."

The shapes and cut were dramatic, and knitwear tops that turned into cowl necks and balaclava-style headgear brought warmth and wit to the show. So did the hats, some trailed by feathers that were three feet long.

Of course, she threw in a few sparkly evening dresses, with a plunging neckline or a backless look, to help make cocktail hour sizzle.

Despite leaving behind the fine weather and natural allure of Brazil, Issa said she finds joy in London, even if the weather is often drab.

"Even when it's misty and fog, it's beautiful," she said. "The shades of grey are fantastic. And it's not misty and foggy all the time."

And she gets a kick out of being part of an A-list fashion crowd, enjoying a reception Friday night at 10 Downing Street with designer Victoria Beckham, American Vogue editor Anna Wintour and other top figures.

Issa denies designing any maternity clothes for the Duchess of Cambridge, who is expecting a baby in July. But she said many of her stretchy dresses are popular with mothers-to-be.